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15. At the end of glycolysis, if no oxygen is present, the pyruvate must either be converted to ethyl alcohol (in yeast) or lactate in muscle cells so that the NADH that was created can get rid of the energized electron and hydrogen ion it is carrying. The electron and hydrogen are given to make either alcohol or lactate. This creates NAD+ which can return to glycolysis to pick up more electrons and hydrogens. This keeps glycolysis going so ATP can be generated in the steps after NADH formation.
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